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Discussion Starter · #1 ·
Hi all, had a service some weeks back and since then my economy has risen noticeably from about 8.2 l/100 to currently 11.1. My driving pattern did change about the same time, I was doing about 40km a day with mostly 70-80 zones (but constantly fanging it) plus toodling around near home, whereas since the service I'm no longer doing that 40k, but just driving around my local suburban area (and less right-foot heavy). It's hard to compare apples with oranges but is that enough to change economy so drastically? I would always giggle about being able to thrash it and still stay around the 8-ish l/100 mark. Just wondering what people think. I know there's a few variables in there. One constant is same servo and petrol, Caltex 98.
 

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Depends how your measuring your fuel economy, are you filling to the first click (or to when it goes to the top of the filler neck) writing down the kms then driving for a bit and filling up to the same level then comparing the fuel economy based on kms and litres filled? Hmm usually your fuel economy gauge on a petrol turbo is the inverse of your boost gauge :D. Are you still doing Jack rabbit starts? My old corolla consistantly get's 7.5L/100kms driving normally, but if I do my usually Jack-rabbit starts to the speed limit it goes to 9.5L/100kms.
 

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8.2L/100km?!?! I am averaging ~6.5L/100km... Have you looked at your trip computer average speed? It might provide some insight into the traffic condition you drive in which may be reflective in your economy. Since your last service, was the engine oil viscosity changed to a thicker grade which may also result in increase fuel use? I doubt just the oil component will result in such significant increase though...
 

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Yeah 8.2L itself is quite high let alone 11.2... I sit in about an hour of <50km/h traffic, crawling up hills in 1st/2nd etc. each way for work and sit on around 7.5. Standard driving really shouldn't see much past the 7L mark.
 

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I've never broken 8.4l per 100km on the street and that's pretty much foot flat everywhere (mix town & highway).

If all things are equal, an increase fuel consumption you would mean a decrease in efficiency. I wonder if they changed your air filter?
 

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or the average reset recently (battery disconnected or you held the trip computer button down on the average fuel consumption display). And it's still figuring your average. Mine currently reads 9.4L/100k.. but disconnected battery the other day to plumb vacuum lines through the symposer tubes for the boost gauge. My normal average is 8.0,I'm pretty much in boost all the time lol, lowest I've had was around 7.3.
 

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Discussion Starter · #7 · (Edited)
Thanks for all the responses. I'm gauging this off the trip computer. I'm pretty sure straight after the service the reading was up to 11-something (whereas when I took it in it was 8-something) and I thought, oh somehow that's got screwed up, so I reset it. When it quickly went back up again, I thought I'd do a fill and reset again. By the end of the tank (yesterday) it was back up to 11.0 (just checked). Again, I have been driving much easier than I ever have until now, and yet it went back up to 11. If Ford screwed something up for me in the service, it won't be the first thing (they did completely the wrong service, for starters, and also pumped up my rear tyres to 33 which is the loaded-up pressure. Don't get me started). I was pretty ok with low-8's economy considering I was nailing it a lot but 11 is over the top. I am running a BlueFin standard tune BTW, but I was well before the service as well. I un-flashed it for the service and re-flashed a day or two after. So I should take it in?

BTW re average speed.. I'm never in bumper-to-bumper traffic. My whole last tank was the usual mix of 40-80 zones. I'll check it though.

PS I'm in awe of anyone getting 6.5l/100 while thrashing it o_O

edit: just booked it back in with Ford. 6 day wait..
 

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Discussion Starter · #8 ·
Depends how your measuring your fuel economy, are you filling to the first click (or to when it goes to the top of the filler neck) writing down the kms then driving for a bit and filling up to the same level then comparing the fuel economy based on kms and litres filled? Hmm usually your fuel economy gauge on a petrol turbo is the inverse of your boost gauge :D. Are you still doing Jack rabbit starts? My old corolla consistantly get's 7.5L/100kms driving normally, but if I do my usually Jack-rabbit starts to the speed limit it goes to 9.5L/100kms.
Pretty much fill it to first click. I have not been writing figures down, just using the trip computer. Jack rabbit starts? You mean basically gunning it off the line? Not since the service, I've been pretty sedate :)
 

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Discussion Starter · #10 ·
never said anything about trashing it... :)
I said thrashing not trashing , but you said neither so point taken :) Hopefully you do give it a bit from time to time ;) otherwise what's the point!

Anyway I've unflashed the tune and reset the trip computer so I'll see how it goes until the service next Wednesday.
 

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In the past with karmen vortex afm's i've cleaned them with carby cleaner and a squirt of air (air not required). They can be fairly delicate so its good to not scrub them or use cleaners that leave residue.
 

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Discussion Starter · #15 ·
Well no word of having to clean the MAF sensor, they reckon it wasn't a sensor issue. The write up:

Checked for engine fuel consumption went from 8 to 11
litres & carried out self test & found communication fault
codes logged when the vehicle started, cleared codes & found no
hard fault codes, reset all parameters and road tested &
found reading 7.7 litres. Customer to monitor

Actually when I got in it was actually in the 8's. It's now up to about 10 and rising. I'll do a test with 2 tanks, measuring and working out consumption manually.
I might run it without the Bluefin tune during that time.
 

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Discussion Starter · #17 · (Edited)
They did not change the air filter nor anything else. Or did you mean during the service?

Just checked the service report, they checked but did not replace. It was the 30k/2yr service. Car was closer to 20k/1yr.
Looks like all they replaced was pollen filter, engine oil & filter and a wheel nut. Everything else was 'checked or inspected'.
 

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I had the same happen to my wife's xtrail and I still have not found the solution. The oil and air filter has been changed many times with different oils and filters to no avail. No idea why this would happen but maybe the MAF clean will help.


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Discussion Starter · #19 ·
I had the same happen to my wife's xtrail and I still have not found the solution. The oil and air filter has been changed many times with different oils and filters to no avail. No idea why this would happen but maybe the MAF clean will help.
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Might suggest that next time I see them.

I'm now sitting steady on about 10.5 l/100. Am not working at the moment so not doing many k's, still on the same tank since my last post, but will check usage myself on the next refill and see what's up.
 

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Discussion Starter · #20 ·
Just another follow up. Just filled up, and on my last tank I got 11.75 l/100 (measured) doing absolutely normal suburban driving, so that's pretty horrendous. I used Caltex 95. I normally use 97 but the last 2 tanks have been 95. Also have kept car stock (no Bluefin) since the service. By the way the car is telling me 10.7 so it's pretty far out. Another call to Ford coming up... Guess I'll suggest a MAF sensor clean.
 
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